(559b) Peptide Nucleic Acid-Mediated Aggregation of Graphene Oxides and Applications in Detection of DNA Mutations

Peptide
nucleic acid-mediated aggregation of graphene oxides and applications in
detection of DNA mutations

Taegyeong
Kang^a, Cheolsang Yoon^a, Hyungjoon Jeon^a, Bumsang
Kim^b, Kyong-Ah Yoon^c, and Kangtaek Lee^a,*

^a
Department of Chemical and Biomolecular
Engineering, Yonsei University, Seoul, Republic of Korea

^b
Department of Chemical Engineering, Hongik
University, Seoul, Republic of Korea

^c
National Cancer Center, Goyang,
Gyeonggi, Republic of Korea

Over the past several years, graphene oxides (GO) has
been extensively studied due to its unique properties and potential
applications in many fields. Recently, it is found that GO can be folded and
aggregated under certain conditions. Herein, we report a simple method to induce
aggregation of GOs in aqueous solution using the peptide nucleic acid (PNA). It
is well known that single-stranded DNAs can easily adsorb onto the GO surface
by non-covalent ¥g-¥g stacking interactions. Therefore, addition of PNA that is a
DNA analogue with a neutral polyamide backbone into the GO suspensions is
expected to result in adsorption of PNA on the surface of GO, which leads to destabilization
and aggregation of GOs. We have investigated aggregation of GOs using optical microscopy,
TEM, and quasi-elastic light scattering. Furthermore, PNA-mediated selective
aggregation of GO was applied to detect mutations in DNA sequence by using PNA
as probe. Using this method, we could successfully detect mutations in DNA
samples with high selectivity and sensitivity.

Figure 1. Schematics of
PNA-mediated selective aggregation of graphene oxides